Conduction system pacing for cardiac resynchronization therapy: a systematic review

Biventricular pacing (BVP) remains the standard method for delivering cardiac resynchronization therapy (CRT) in patients with heart failure and left bundle branch block (LBBB). Despite its established role, BVP is a non-physiological pacing approach and is limited by factors such as anatomical constraints of the coronary sinus and a substantial proportion of non-responders. Conduction system pacing (CSP), including His bundle pacing and left bundle branch area pacing, has emerged as a more physiological alternative aimed at optimizing CRT outcomes. Early studies suggest that CSP may achieve superior electro-mechanical ventricular synchrony compared with BVP. Nevertheless, evidence from large-scale randomized controlled trials remains scarce, and challenges related to procedural complexity and insufficient long-term outcome data currently prevent CSP from replacing BVP as the first-line CRT strategy. This systematic review synthesizes the existing literature on CSP in CRT, explores its potential applications across different clinical contexts, and discusses the ongoing controversies and future prospects of this evolving technique.